Bug 2552941

Description of problem:
When booting Fedora cloud-init image with user-data containing ntp configuration, ntp configuration fails to get applied due to cloud-init trying to restart a service named `chrony` rather than `chronyd`.
I was able to reproduce this on Fedora 43 as well but bugzilla only allows me to select one version.

Version-Release number of selected component (if applicable):
cloud-init-25.3-3.fc44.noarch

How reproducible:
Always

Steps to Reproduce:
1. Create a VM with the Fedora 44 cloud-init image using the following user-data (I tested locally with https://download.fedoraproject.org/pub/fedora/linux/releases/44/Cloud/x86_64/images/Fedora-Cloud-Base-Generic-44-1.7.x86_64.qcow2):
```
#cloud-config
ntp:
  pools: ["pool.ntp.org"]
users:
  - default
  - name: vm
    plain_text_passwd: vm
    lock_passwd: false
    sudo: ALL=(ALL) NOPASSWD:ALL
    shell: /bin/bash
```
2. Once cloud-init finishes running, you should see the issue in boot logs. You can also try logging in with vm:vm and run `sudo cloud-init status -l` to see the same error.

Actual results:
cloud-init ntp module failed to restart the service due to wrong name being used.
Here's a short excerpt from the boot logs:
```
[  OK  ] Reached target multi-user.target - Multi-User System.
[    8.373325] cloud-init[882]: Cloud-init v. 25.3 running 'modules:config' at Wed, 14 Oct 2026 20:24:59 +0000. Up 8.36 seconds.
[    8.383909] cloud-init[882]: 2026-10-14 20:24:59,454 - cc_ntp.py[ERROR]: Failed to reload/start ntp service: Unexpected error while running command.
[    8.384635] cloud-init[882]: Command: ['systemctl', 'reload-or-restart', 'chrony']
[    8.385033] cloud-init[882]: Exit code: 5
[    8.385254] cloud-init[882]: Reason: -
[    8.385468] cloud-init[882]: Stdout:
[    8.385671] cloud-init[882]: Stderr: Failed to reload-or-restart chrony.service: Unit chrony.service not found.
[    8.386166] cloud-init[882]: Traceback (most recent call last):
[    8.386472] cloud-init[882]:   File "/usr/lib/python3.14/site-packages/cloudinit/config/cc_ntp.py", line 623, in handle
[    8.386995] cloud-init[882]:     cloud.distro.manage_service(
[    8.387295] cloud-init[882]:     ~~~~~~~~~~~~~~~~~~~~~~~~~~~^
[    8.387587] cloud-init[882]:         "reload", ntp_client_config["service_name"]
[  OK  ] Finished cloud-config.service - Cloud-init: Config Stage.
[    8.388332] cloud-init[882]:         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[    8.388703] cloud-init[882]:     )
[    8.388897] cloud-init[882]:     ^
[    8.389096] cloud-init[882]:   File "/usr/lib/python3.14/site-packages/cloudinit/distros/__init__.py", line 1384, in manage_service
         Starting cloud-final.service - Cloud-init: Final Stage...
[    8.390015] cloud-init[882]:     return subp.subp(cmd, capture=True, rcs=rcs)
[    8.390646] cloud-init[882]:            ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[    8.391046] cloud-init[882]:   File "/usr/lib/python3.14/site-packages/cloudinit/subp.py", line 291, in subp
[    8.391549] cloud-init[882]:     raise ProcessExecutionError(
[    8.391850] cloud-init[882]:         stdout=out, stderr=err, exit_code=rc, cmd=args
[    8.392232] cloud-init[882]:     )
[    8.392605] cloud-init[882]: cloudinit.subp.ProcessExecutionError: Unexpected error while running command.
[    8.393097] cloud-init[882]: Command: ['systemctl', 'reload-or-restart', 'chrony']
[    8.393477] cloud-init[882]: Exit code: 5
[    8.393742] cloud-init[882]: Reason: -
[    8.393942] cloud-init[882]: Stdout:
[    8.394991] cloud-init[882]: Stderr: Failed to reload-or-restart chrony.service: Unit chrony.service not found.
[    8.396516] cloud-init[882]: 2026-10-14 20:24:59,455 - log_util.py[WARNING]: Running module ntp (<module 'cloudinit.config.cc_ntp' from '/usr/lib/python3.14/site-packages/cloudinit/config/cc_ntp.py'>) failed
[    8.408106] cloud-init[882]: Cloud-init v. 25.3 running 'modules:final' at Wed, 14 Oct 2026 20:24:59 +0000. Up 8.40 seconds.
```
and output from `sudo cloud-init status -l`:
```
[vm@localhost ~]$ sudo cloud-init status -l
status: error
extended_status: error - done
boot_status_code: enabled-by-generator
last_update: Thu, 01 Jan 1970 00:00:08 +0000
detail: DataSourceNoCloud [seed=dmi,/dev/sr0][dsmode=local]
errors:
	- ('ntp', ProcessExecutionError("Unexpected error while running command.\nCommand: ['systemctl', 'reload-or-restart', 'chrony']\nExit code: 5\nReason: -\nStdout: \nStderr: Failed to reload-or-restart chrony.service: Unit chrony.service not found."))
recoverable_errors:
ERROR:
	- Failed to reload/start ntp service: Unexpected error while running command. Command: ['systemctl', 'reload-or-restart', 'chrony'] Exit code: 5 Reason: - Stdout:  Stderr: Failed to reload-or-restart chrony.service: Unit chrony.service not found.
WARNING:
	- Running module ntp (<module 'cloudinit.config.cc_ntp' from '/usr/lib/python3.14/site-packages/cloudinit/config/cc_ntp.py'>) failed
```

Expected results:
I expected cloud-init to succeed with no errors.

Additional info:
Potentially relevant issue upstream from few years ago: https://github.com/canonical/cloud-init/issues/3756
Seems like the fix included RHEL but missed Fedora though: https://github.com/canonical/cloud-init/blob/8537237d80a48c8f0cbf8e66aa4826bbc882b022/cloudinit/config/cc_ntp.py#L121-L127